On the whole, I was a fan of Katsa, her abilities, and the manner in which she contemplated and dealt with them. I particularly enjoyed the character development achieved by a growing and amusing friendship.
However, about the point in the book where Po and Katsa's relationship turns physical, I started noticing things. First was that, though Katsa chose the role of lovers over becoming spouses because it would allow her more freedom, control, being her own person, etc., I detected a very distinct shift in her character as well as in the writing once she made that decision. This new role changed her, not necessarily for the better. Thankfully, I did not experience another Song of the Lioness "is there anyone she hasn't slept with?" moment, but I still found that stretch of time alone in the forest to be one of the weaker portions of the story. I would much rather have seen a further developing of their friendship, still supposedly new and unfamiliar territory for the lady killer. Katsa didn't feel like Katsa again until after she'd left Po behind and started climbing mountains. (Also, Po occasionally felt a little too perfect, too angsty, and/or too Edward Cullen. Not all the time, but it happened.)
There were also a number of settings/characters of which I would have liked to see more, but better limiting the scope of the story than going for too much and bungling it or scaring readers off with a ridiculous page count.
Overall, minus that one section, I enjoyed the story and would consider picking up one of its spin-offs.
Interesting side note: I found the name of the lady whose dogs I am currently watching (and who was one of my college writing profs) in the Acknowledgements section. Coolness. :)
Edit: I realized something the day after writing this review ... and then forgot about adding it here for half a month. That portion of the story near the end where Po is being a moody, blind woodsman aching to be alone with nature once more? There's a 90's animated movie theme song for that! Anyone remember "I Stand Alone" from "Quest for Camelot"? Yep.